www.ukbutterflies.co.uk

Just ordered mine
I've been thinking about it for ages deciding what to do as I already have the Sigma 105 and 150
I think it will be perfect for butterflies and natural light macro stuff as I dont like using flash
Mainly will be shooting butterflies which will be about half lifesize . What sort of shutter speeds will I get away with ?
Im guessing at 60th at half life size and about 125th at 1:1 should be OK and lower with practice
I was thinking about getting the Canon 100mm before the IS version came out as I prefer autofocus to manual as I'm a bit slow focussing manually. By the time I've got the focus the butterfly will have gone and the Sigma 105 is slow on autofocus too ! And mine was starting to get faulty a few times just made a wirring noise instead of focussing.
I hope its as sharp as my Sigma's they get superbly sharp shots
Pete

Oh it is sharp, but I can't say much more as there aren't many subjects at the moment. I changed my Tokina for the new Canon a couple of month back. Not really for macro performance, but to add a short tele with IS.

I read reviews that said that because of the USM and IS and slightly faster focusing, the Canon 100mm IS L Macro is a bit better than Sigma 105mm, but from what reviews I have read, people like both lenses, so its hard to tell which is actually better overall as I could not find somewhere that said which is better

Thanks it arrived the other day
I Put it on the 40D and tried some shots indoors and its amazing for portraits I can handhold at 1/30 shutter speed
I do natural light macros as well as butterflies and recon it will be perfect
Also my 105 has an intermittent fault with the autofocus and gives me an excuse to get a new lens

Cant wait for the season to start
Pete

Well Pete, can't wait to see what shots you get with your new lens if I had that kind of spare money, I'd get one myself, but I can only dream right now...anyway my Sigma 105mm EX DG Macro is still quite good so I am not really complaining.

I cant wait for the season to start either
I had to work loads of overtime to pay for it , I dont have any other vices so went for it
Pete